The Health Foundation charity stressed that a no-deal Brexit could lead to "a vicious, and avoidable, combination of risks" as the country continues its fight against the COVID-19 pandemic.
A majority of people in Britain support extending the Brexit transition period because of the COVID-19 pandemic, new research has found.
More than half — 54% — of the nearly 2,000 British people surveyed by pollster Ipsos MORI for the Health Foundation charity said the UK should request an extension to the transition period in order for the government to focus on the COVID-19 pandemic.
The proportion of people supporting the extension rose to 65% when informed that there could be potential delays to the supply of medicines and medicinal products in the event of a no-deal Brexit, in line with government assessments.
Over three-quarters of people surveyed also believe the UK should work "very closely" with the EU to combat COVID-19, with a further 17% agreeing it should work "fairly closely" with the bloc.
The UK formally exited the European Union on January 31 and entered into a transition period —agreed upon to leave more time for the two sides to reach a deal — which is scheduled to expire on December 31 2020.
Britain had until the end of June to notify the EU whether it wished to extend the transition period but Cabinet Minister Michael Gove said on Friday that he had already "formally confirmed" the UK will not do so.
"On 1 January 2021 we will take back control and regain our political and economic independence," he added on Twitter.
Negotiations have so far been tortuous with EU negotiator Michel Barnier arguing that "the UK has taken three steps back from the commitment it originally made", while his British counterpart, David Frost, said the main stumbling block "is the EU's insistence on including a set of novel and unbalanced proposals on the so-called "level-playing field"."
UK Prime Minister Boris Johnson, European Commission President Ursula von der Leyen, and EU Council chief Charles Michel are to hold talks on Monday. The virtual meeting was announced after a fourth round of negotiations failed to produce substantial progress.
Not reaching a deal in time would mean moving to WTO trade rules and resuming customs checks, which could have severe implications on the island of Ireland where people and goods can cross the border between Northern Ireland and the Republic unhindered thanks to the Good Friday Agreement of 1998.
Jennifer Dixon, Chief Executive of the Health Foundation, also warned that "this winter a no-deal Brexit could exacerbate already acute shortages in the NHS [National Health Service] and social care workforce and create new avoidable shortages of medicines and supplies."
"This would come at the same time as the health service is facing significant pressures from seasonal flu, supporting people recovering from COVID-19, tackling the large backlog of patients who didn't receive care during lockdown, and potentially coping with another wave of infection from the coronavirus. This would be a vicious, and avoidable, combination of risks," she added.
According to an internal pharmaceutical industry memo prepared in May for the British government and seen by the BBC last week, some stockpiles of medical supplies have been "used up entirely" to respond to COVID-19.